Email this article ERRORS IN FITTING RADIAL DOSE FUNCTION OF COBALT SOURCES FOR BRACHYTHERAPY WITH 3-5 DEGREE POLYNOMIALS
- Authors: Belousov A.V.1,2, Belyanov A.A.1,2, Chernyaev A.P.1,3,4
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Affiliations:
- Lomonosov Moscow State University
- 1 Leninskie gory, Moscow, 119991, Russian Federation
- 1 Leninskie gory, Moscow, 119991, Russian Federation Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University
- 1 Leninskie gory, Moscow, 119991, Russian Federation
- Issue: Vol 44, No 2 (2016)
- Pages: 140-147
- Section: ARTICLES
- URL: https://almclinmed.ru/jour/article/view/330
- DOI: https://doi.org/10.18786/2072-0505-2016-44-2-140-147
- ID: 330
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Abstract
Background: Providing quality insurance for radiation therapy implies high level of precision for determining absorbed dose, and therefore high level of precision for fitting radial dose function. 3-5 degree polynomials provide required precision, however, uncertainty of their coefficients may cause substantial errors. Aim: To investigate dependence of errors of calculating radial dose function with consideration of uncertainty of coefficients from different degrees of fitting polynomial. Materials and methods: Calculations were performed with software package GEANT4.9.6. Geometry and materials of the source correspond to the model BEBIGCo0.A86. Spectral structure of the source corresponds to the NuDat 2.6 database. Statistical processing was done using nonlinear least-square method. Results: Values of the radial dose function of Cobalt source for brachytherapy were calculated for given geometry. Conducted comparison of precisions of 3 to 5 degree polynomial approximations and possible uncertainties of results of radial dose function calculations. Conclusion: Withrequired precision of 25% and higher at the radius of 10 cm the optimal choice for radial dose approximation is the 3rd degree polynomial.
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About the authors
A. V. Belousov
Lomonosov Moscow State University; 1 Leninskie gory, Moscow, 119991, Russian Federation
Author for correspondence.
Email: belousovav@physics.msu.ru
PhD (in Physics and Mathematics), Associate Professor, Chair of Physics of Accelerators and Radiation Medicine, Faculty of Physics Russian Federation
A. A. Belyanov
Lomonosov Moscow State University; 1 Leninskie gory, Moscow, 119991, Russian Federation
Email: belousovav@physics.msu.ru
Junior Research Fellow, Chair of Physics of Accelerators and Radiation Medi- cine, Faculty of Physics Russian Federation
A. P. Chernyaev
Lomonosov Moscow State University; 1 Leninskie gory, Moscow, 119991, Russian FederationSkobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University; 1 Leninskie gory, Moscow, 119991, Russian Federation
Email: belousovav@physics.msu.ru
PhD (in Physics and Mathematics), Professor, Head of the Chair of Physics of Accelerators and Radiation Medicine, Faculty of Physics, Head of the Laboratory of Beam Technolo- gies and Medical Physics
Russian FederationReferences
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